Yes, small boy from Avengers episode played there, exactly as one of Fagin's Boys:

According to Spotlight, Clive Moss also participated in following works:

TV series

Court Martial

Movies

1. Up Jumped a Swagman

2. The Nanny

3. One Million Years B.C.

4. Operation Third Form

5. The Spy with a Cold Nose

6. Fahrenheit 451

7. The Christmas Trees

8. Quiller Memorandum

9. Charlie Bubbles

10. Half a Sixpence

Hmm, this time I could not find his in the mentioned works by Aveleyman and Moviedude.

It seems to be necessary to personally watch some of these films, since I'm sure that his identification in the episode "Alf's Broken Leg" of TV series "Til Death Do Us Part" is true._________________Russian fan-site Steedumbrella.
http://steedumbrella.ru

His face doesn't ring a bell, but thank you for Clive Moss, I'd missed that update until now._________________Mrs Peel, you're needed!
http://www.dissolute.com.au/the-avengers-tv-series/
Every episode from 1961 to 1977 plus more trivia than you can shake a brolly at.

Just found out what turns, according to newspaper The Observer from January 23, 1966, well-known actor Howard Pays played in The Avengers.

There it is also mentioned that he was in "The Saint" that on moment is not indicated on IMDb and other TV and movie sites, too. Although of course his role could be uncredited or cut or something else.

Yes, small boy from Avengers episode played there, exactly as one of Fagin's Boys:

According to Spotlight, Clive Moss also participated in following works:

TV series

Court Martial

Movies

1. Up Jumped a Swagman

2. The Nanny

3. One Million Years B.C.

4. Operation Third Form

5. The Spy with a Cold Nose

6. Fahrenheit 451

7. The Christmas Trees

8. Quiller Memorandum

9. Charlie Bubbles

10. Half a Sixpence

Hmm, this time I could not find his in the mentioned works by Aveleyman and Moviedude.

It seems to be necessary to personally watch some of these films, since I'm sure that his identification in the episode "Alf's Broken Leg" of TV series "Til Death Do Us Part" is true.

I have been told that the small boy is Steven Morley, also credited in Oliver! but I can find no independent corroboration of that._________________Mrs Peel, you're needed!
http://www.dissolute.com.au/the-avengers-tv-series/
Every episode from 1961 to 1977 plus more trivia than you can shake a brolly at.

A face identical to the actor who is listed on the Moviedude as Steve Morley:

In his early career he was known as Steven Morley, and if he was actually born in 1953, then he should have been about 12 years in the Avengers. and our boy looks like a preschooler._________________Russian fan-site Steedumbrella.
http://steedumbrella.ru

Now I'm bit re-reading the book The Ultimate Avengers (Dave Rogers) and just found a forgotten info about that the mother of the director Lewis Gilbert participated as an extra in The Avengers (it is possible that Lewis said about, considering that his mother died in 1972).

I don't recognise Oliver but there's a great photo from 1967 in my '68 Spotlight, I'll post it when I can._________________Mrs Peel, you're needed!
http://www.dissolute.com.au/the-avengers-tv-series/
Every episode from 1961 to 1977 plus more trivia than you can shake a brolly at.